Is it possible to combine two textures?
Yes, you can in many ways. You can just mix RGB:


Or similarly you can mix shaders (here the effect is the same, but with different Principled BSDF settings it would differ):

Or you can do something more interesting:


If you have some specific textures in mind and a specific way to merge them, it would be good if you described them in your question. A texture with scratches could be added based on it's alpha channel for example.